Little could an Australian teenager have known about the tragic result of eating a raw slug as a “dare”.

Back in 2010, then 19-year-old rugby player Sam Ballard was at a party with his friends when he was dared to eat a slug found in the garden. But it turned out that that slug was infected with a parasitic worm, which has left him quadriplegic.

The parasite, called Angiostrongylus cantonensis, is more commonly known as rat lungworm. As their name suggests, these worms are usually found living in the lungs of rodents where they mature, forcing the rats to cough them up into their throats before swallowing the adults. These nematodes then move through the digestive tract of the rodent, before being pooped out the other end.

It is at this point that slugs and snails become infected, as they feed on the rat poop containing the worms. Usually, the gastropods are then eaten by the rats and the cycle starts again. But in some cases, the infected slugs and snails are eaten by other things that can harbor the parasite, such as frogs, shrimps, and crabs. And occasionally humans.

There have been a few cases of people contracting rat lungworm in the past, but none with quite such a devastating end. In 1993, for example, a young boy in New Orleans ate a raw snail – again as a “dare” – and came down with muscle aches, a slight fever, and vomiting, but managed to clear the infection within a few weeks.

In the case of the unfortunate teenager in Australia, however, the passage of the parasitic worm into the nervous system and eventually the brain tissue led to the development of eosinophilic meningoencephalitis. As a result, Ballard fell into a coma for 420 days, and upon waking was no longer able to use any of his limbs and required a feeding tube. Eight years on, and he still requires around-the-clock care.

Unfortunately, this care has come at a heavy price for the family, who are quickly running out of funds to support Ballard. A situation made all the worse by the fact that the Australian government has now slashed the amount of aid it was planning on giving them as a way to help alleviate these expenses.

Rat lungworm is prevalent throughout East Asia, Australasia, and the Pacific Islands, but has also been found in parts of Africa, the Caribbean, and the United States. It is recommended that, obviously, you don't eat raw slugs and snails. You should also wash any green veg that might be hiding them, and make sure that other foods like frogs, shrimp, and crabs are fully cooked before eating them.